Concentrate mainly on the three you mentioned but pull-ups will not hurt. So long as training at pull-ups does not detract from pushups, situps, or running, I say have at it. All it will do is make you more fit.
When you block a person, they can no longer invite you to a private message or post to your profile wall. Replies and comments they make will be collapsed/hidden by default. Finally, you'll never receive email notifications about content they create or likes they designate for your content.
Note: if you proceed, you will no longer be following .